1. Field of the Invention
The present invention relates to a cooling fluid pump for cooling an object to be cooled by contacting the object to an outer surface of a casing. The invention more particularly relates to a cooling pump used in a cooling device for cooling a heating member of an electrical appliance such as a computer.
2. Description of the Related Art
A fluid pump is composed of a casing having a pump chamber inside, a suction port and a discharge port provided in the casing and an impeller arranged rotatably in the pump chamber having pump vanes and pump grooves. A liquid suctioned into the pump chamber from the suction port by rotation of the impeller flows through a fluid path and is discharged from the discharge port. A protrusion is provided in an area in between the suction port and the discharge port in the fluid path and the protrusion applies pressure to the liquid flowing through the fluid path.
The fluid pump having such configuration is described in JP-A-2001-123978 and JP-A-2001-132677.
In case the fluid pump is used as a cooling device for a CPU, which is a heat generating member of an electronic appliance for example, a personal computer, the CPU is mounted on the casing of the pump via a heat diffusing plate. Such configuration conveys the heat generated by the CPU to the casing via the heat diffusing plate and releases the heat by exchanging the heat between the casing and the liquid flowing through the fluid path.
Therefore, in order to efficiently cool the heat generation member, the heat exchange rate between the objects to be cooled such as the heat generating member and the heat diffusing plate and the liquid flowing through the fluid path needs to be improved.